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The world of pipe fittings

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Re: The world of pipe fittings

#261

Post by nickpinkston »

Tijdreiziger wrote: post #26
blincoln wrote: post #12

I've helped out with some plumbing work in an older house, and it's pretty fascinating to see the progression of technologies. 100 years ago, most drain pipes in the US were massive cast-iron pieces with no threads at all. They were mated together, then the joint was filled with a compound called oakum. To really hold it together, the plumber would pour molten lead on top of the oakum. Just taking that stuff apart is…

> To really hold it together, the plumber would pour molten lead on top of the oakum. This is pretty interesting, because plumbers are called 'lead-pourers' (loodgieters) in Dutch, and I had always wondered why.

The word comes from Roman Latin because their pipes were mostly made from lead, and even had standardized fitting/valve sizes, etc.

https://www.wavin.com/en-en/news-cases/news/the-roman-empire...

Re: The world of pipe fittings

#262

Post by shellfishgene »

jkqwzsoo wrote: post #9

In case anyone from the US reads this, BSPP and BSPT fittings are rare and incredibly frustrating here, as our NPT (National Pipe Taper) threads are different and the selection of BSP(P/T) fittings is extremely poor in comparison. Also, I work with NPT fittings quite a lot: > For what it’s worth, I tightly wrap the tape 10 times round the male thread and get an enraged mountain gorilla to tighten it up. This is a WTF…

In Germany using hemp fibers instead of the PTFE tape is still really common (together with a sealing paste calle Neo-Fermit). The disadvantage of the tape is that you can't turn the fitting backwards even a little bit when tightening it, or you get leaks. With hemp that does not matter so much as it swells up with water.

Re: The world of pipe fittings

#263

Post by mindslight »

bombela wrote: post #251
mindslight wrote: post #52

Earlier quoted context omitted.

Thinking about a system a half-step up from hose clamps holding 100psi of pressure, which if it pulls apart will rapidly release hundreds of gallons of water does not inspire confidence. And since the house is already plumbed with copper and I know how to sweat joints, I might as well continue that. I'm about to use PEX for the first time on my hydronic heating system, which is only ~20psi and limited volume (autofil…

There is few type of PEX fitting systems. I agree the hose clamp style doesn't inspire confidence at all. I have replaced almost all piping in my house. I used PEX-B with the fittings secured by copper rings that you crimp with the appropriate tool. It is so easy to use and confirm the joint with a gauge tool. I had to solder copper where I couldn't replace it all. Every copper joint was it's own little project. Whil…

After a thorough session of Internet Research, I chose to start with stainless cinch rings rather than the copper crimp rings? Because copper crimp rings are seemingly preferred by professionals only due to being slightly cheaper in quantity plus looking nicer? Also the consumer-priced power tool (Ryobi) for doing the crimp rings has mixed reviews, while their cinch ring tool seems universally loved (likely due to manufacturing tolerances needed for a good crimp die).

Either way, my lack of confidence applies to all PEX-B and PEX-A connections. They're all essentially a straight friction fit with some hose barbs. I got some PEX-AL-PEX fittings/tube too (the 1" P-A-P has 35% larger cross section than plain PEX, and PEX larger than 1" seems rare and expensive), and the threaded compression style gives more confidence.

I'm not disputing that PEX is a whole lot easier, even knowing how to do copper and just watching PEX videos. As I said, "maybe I'll fall in love". I'm just starting with piping where a leak won't be a major hassle (hydronic, and eventually compressed air), and foresee myself continuing to do copper for any modifications to potable water in the immediate future. If I had to redo the whole house, I'd get over my reservations quick!

Re: The world of pipe fittings

#264

Post by bombela »

mindslight wrote: post #263
bombela wrote: post #251

Earlier quoted context omitted.

There is few type of PEX fitting systems. I agree the hose clamp style doesn't inspire confidence at all. I have replaced almost all piping in my house. I used PEX-B with the fittings secured by copper rings that you crimp with the appropriate tool. It is so easy to use and confirm the joint with a gauge tool. I had to solder copper where I couldn't replace it all. Every copper joint was it's own little project. Whil…

After a thorough session of Internet Research, I chose to start with stainless cinch rings rather than the copper crimp rings? Because copper crimp rings are seemingly preferred by professionals only due to being slightly cheaper in quantity plus looking nicer? Also the consumer-priced power tool (Ryobi) for doing the crimp rings has mixed reviews, while their cinch ring tool seems universally loved (likely due to ma…

PEX-AL-PEX is more expensive, but also convenient to work with as it stays in place like a gooseneck lamp. It is also an oxygen barrier, and as such useful for closed loop hydronic with prone to rust components (cast iron). I don't know if P-A-P can be rated for potable water though.

I purposefully avoided the stainless cinch rings. This feels like the cheapest solution to me. It has some moving pieces. I found examples of leak with stainless cinch rings online when I was choosing what technology to use. Not so much with the copper rings. The copper rings are just that. A thick copper ring that you press into shape with great force. The price of the $50 crimp tool is nothing compared to the cost and hassle of a leak down the line. Add a $30 ring cutter tool too. For when you mess up (you cannot remove the ring in place, you must cut the pipe).

I have also retrofitted the house with underfloor hydronic heating. 400m of PEX in an open loop system. Not a single leak after few years.

With the copper rings the PEX takes the shape of the fitting. Even if you manage to cut the ring. The PEX won't come off. You have to cut the pipe lengthwise to get it off. I am not sure the stainless clamps perform the same.

Re: The world of pipe fittings

#265

Post by mindslight »

bombela wrote: post #264
mindslight wrote: post #263

Earlier quoted context omitted.

After a thorough session of Internet Research, I chose to start with stainless cinch rings rather than the copper crimp rings? Because copper crimp rings are seemingly preferred by professionals only due to being slightly cheaper in quantity plus looking nicer? Also the consumer-priced power tool (Ryobi) for doing the crimp rings has mixed reviews, while their cinch ring tool seems universally loved (likely due to ma…

PEX-AL-PEX is more expensive, but also convenient to work with as it stays in place like a gooseneck lamp. It is also an oxygen barrier, and as such useful for closed loop hydronic with prone to rust components (cast iron). I don't know if P-A-P can be rated for potable water though. I purposefully avoided the stainless cinch rings. This feels like the cheapest solution to me. It has some moving pieces. I found examp…

Why open loop for the radiant? Already had non-barrier PEX? Or using existing DHW as the heat source?

I'm installing an outdoor wood boiler, which is an open system. But it will have a heat exchanger to my closed hydronic system for house distribution.

P-A-P seems nicer to route the pipe, but there are fewer fitting shapes. I'm considering it for a few long runs, because anything over 1" nominal seems to become rare and jump in price, and the 1" P-A-P is 35% larger than 1" PEX-B. But maybe I should just suck it up and deal with 1.25 or 1.5 inch PEX-B. (Would you happen to know a good source? I keep coming up with Supplyhouse.com, but half the fittings are out of stock and they seem expensive).

I'll see how I like the cinch rings. Maybe I'll move towards the crimp rings down the line. I figured a powered tool would be a boon for doing a bunch, and as I said it seems like for a powered crimp ring thing I'd need a Milwaukee cordless for ~$600, whereas the cinch ring I can get away with a $100 Ryobi. I can justify the latter for personal use, but not the former.

Re: The world of pipe fittings

#266

Post by berjin »

jakewins wrote: post #182
berjin wrote: post #171

Earlier quoted context omitted.

If you want a really good seal you wrap the tape 1-2 overlaps at the start of the thread and progressively make it thicker and thicker so you have more overlaps (10x) at the base. I guess it depends on the fittings but some run out of tapper and you can't tighten it anymore without the hexagonal nut hitting the adjacent fitting. This works well as you're building your own tapper which is sort of acting as an o-ring.…

Do you have a reference for this? Everything I've read is the purpose of the tape is to reduce friction (hence PTFE), not to actually seal. In other words, the seal comes from the fittings connecting tightly, made possible by 2-3 wraps of PTFE low friction tape.

A reference? This is plumbing not academia. The parts I get might be slightly different than the spec so you have to make up for it with the right amount of tape in situ. If you tighten the threads as much as possible and there is still a gap then you have to seal it somehow. Soft plastics will deform enough to seal without any tape at all but harder materials need something between to fill in the gaps.

Re: The world of pipe fittings

#267

Post by duckmysick »

bombela wrote: post #264
mindslight wrote: post #263

Earlier quoted context omitted.

After a thorough session of Internet Research, I chose to start with stainless cinch rings rather than the copper crimp rings? Because copper crimp rings are seemingly preferred by professionals only due to being slightly cheaper in quantity plus looking nicer? Also the consumer-priced power tool (Ryobi) for doing the crimp rings has mixed reviews, while their cinch ring tool seems universally loved (likely due to ma…

PEX-AL-PEX is more expensive, but also convenient to work with as it stays in place like a gooseneck lamp. It is also an oxygen barrier, and as such useful for closed loop hydronic with prone to rust components (cast iron). I don't know if P-A-P can be rated for potable water though. I purposefully avoided the stainless cinch rings. This feels like the cheapest solution to me. It has some moving pieces. I found examp…

Can you tell me more how you retrofitted your house with underfloor hydronic heating? How long did it take and what materials did you use. How many pipes per square meter? Also, did you reuse the flooring after or did you replace it completely?

I'm looking into adding underfloor heating myself.

Re: The world of pipe fittings

#268

Post by bombela »

duckmysick wrote: post #267
bombela wrote: post #264

Earlier quoted context omitted.

PEX-AL-PEX is more expensive, but also convenient to work with as it stays in place like a gooseneck lamp. It is also an oxygen barrier, and as such useful for closed loop hydronic with prone to rust components (cast iron). I don't know if P-A-P can be rated for potable water though. I purposefully avoided the stainless cinch rings. This feels like the cheapest solution to me. It has some moving pieces. I found examp…

Can you tell me more how you retrofitted your house with underfloor hydronic heating? How long did it take and what materials did you use. How many pipes per square meter? Also, did you reuse the flooring after or did you replace it completely? I'm looking into adding underfloor heating myself.

The house is a stick framing atop a perimeter foundation, with few posts making a crawl space. You can almost sit down. It took a week to install loops of 1/2 (16mm) PEX between the joists supporting the floor. The pipes go through holes in the joist and blocking, and cross at the beginning of every bay to make up every loop. The PEX is held up by aluminum heat plates that are simply stapled. Theost annoying part of the job was to cut all protiding nails. The took few days prior the piping. There is something like 400m of pipes. Split into multiple circuits. Aligned at room boundaries and adjusted to have similar length for homogenous pressure drop. All of that is an open loop with the water heater. A pump, a thermostat and few check valves supply the manifold that distribute the hot water under the floor.

Re: The world of pipe fittings

#269

Post by bombela »

mindslight wrote: post #265
bombela wrote: post #264

Earlier quoted context omitted.

PEX-AL-PEX is more expensive, but also convenient to work with as it stays in place like a gooseneck lamp. It is also an oxygen barrier, and as such useful for closed loop hydronic with prone to rust components (cast iron). I don't know if P-A-P can be rated for potable water though. I purposefully avoided the stainless cinch rings. This feels like the cheapest solution to me. It has some moving pieces. I found examp…

Why open loop for the radiant? Already had non-barrier PEX? Or using existing DHW as the heat source? I'm installing an outdoor wood boiler, which is an open system. But it will have a heat exchanger to my closed hydronic system for house distribution. P-A-P seems nicer to route the pipe, but there are fewer fitting shapes. I'm considering it for a few long runs, because anything over 1" nominal seems to become rare…

pexuniverse and supplyhouse are the two places I have used for the material.

Open loop is easy to deal with. I can use the same water heater. It's the bay area in California, so the system works for 1/3 or the year. Rest of the time it's simply buffering the cold water supply to the water heater. So no water stagnating, not air vent needed, and it's always filled up by definition. Further more because it's at the street water pressure, the pump cannot cavitate, so it last longer and is quieter.

I only used manual tools to crimp the rings. Sure you need some force but your body will build muscles. And since PEX is flexible you don't use that many fittings anyways. It's really childs play.

Re: The world of pipe fittings

#270

Post by duckmysick »

bombela wrote: post #268
duckmysick wrote: post #267

Earlier quoted context omitted.

Can you tell me more how you retrofitted your house with underfloor hydronic heating? How long did it take and what materials did you use. How many pipes per square meter? Also, did you reuse the flooring after or did you replace it completely? I'm looking into adding underfloor heating myself.

The house is a stick framing atop a perimeter foundation, with few posts making a crawl space. You can almost sit down. It took a week to install loops of 1/2 (16mm) PEX between the joists supporting the floor. The pipes go through holes in the joist and blocking, and cross at the beginning of every bay to make up every loop. The PEX is held up by aluminum heat plates that are simply stapled. Theost annoying part of…

Awesome, thanks. The loop design looks simple, which is encouraging. It's true that the most annoying parts are usually the secondary tasks that can't be ignored either way.

The joists sure help. In my case the floor is either tiles or wood panels laying on top of poured concrete.

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